Adjustable wrench for adjusting the width of the jaw quickly

ABSTRACT

An adjustable wrench for quickly adjusting the width of a jaw thereof, comprising a stationary body ( 1 ), having a chamber ( 12 ) at an upper portion thereof; a movable body ( 2 ), having a worm ( 13 ) at a lower portion thereof, being movable transversely inside the chamber ( 12 ); a driving mechanism ( 100 ) located within the chamber ( 12 ), including a worm gear ( 10 ) with a worm gear shaft ( 20 ), engaging the worm ( 13 ), a first gear ( 3 ) mounted at an end of the worm gear shaft ( 20 ) of the worm gear ( 10 ), a connection shaft ( 9 ) located under the worm gear shaft ( 20 ) in parallel, and a second gear ( 4 ) mounted at an end of the connection shaft ( 9 ) to engage with the first gear ( 3 ); and a traction mechanism ( 200 ) connected to the connection shaft ( 9 ), the traction mechanism ( 200 ) driving the second gear ( 4 ) to rotate by driving the connection shaft ( 9 ), which drives the first gear ( 3 ) to rotate, hereby rendering the worm ( 13 ) to move inside the chamber ( 12 ). The adjustable wrench in accordance with the present invention can be adjusted rapidly in the width of the jaw, and is easy to operation with a single hand.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a U.S. National Stage of PCT/CN2003/000829 filedSep. 28, 2003, which claims priority to Chinese Application No.03214884.4 filed Jan. 23, 2003, which applications are incorporatedherein by reference in their entireties.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to an adjustable wrench for quicklyadjusting width of the jaw thereof. The width of the jaw of the wrenchcan be quickly adjusted to a desired size by simply moving a movablebody of the wrench.

2. Description of the Prior Art

A conventional adjustable wrench comprises a movable body and astationary body. A worm mechanism is provided at a lower portion of themovable body. A square hole is disposed in the stationary body toreceive a section of the worm mechanism of the movable body. A worm gearis provided within the square hole to engage a worm of the movable body.When a user manually rotates the worm gear, the worm can move in aleft-and-right direction corresponding to the rotation of the worm gear,which in turn drives the movable body to move in the same direction,thereby adjusting the width of a jaw of the wrench.

The adjustable wrench having the aforesaid configuration is relativelysimple in construction and convenient for use. However, such a wrenchhas disadvantages that when the width required to be adjusted isrelatively large, the worm gear must be turned frequently. For example,if a large size wrench is used in exploitation of oil where a relativelylarger pipe or nut needs to be turned, it is necessary to turn the wormrepeatedly to give a full jaw travel. Furthermore, it is difficult toreliably hold an object by manually adjusting the width of the jaw.

In order to solve these problems, Chinese Patent No. CN2196532 with atitle of “a quickly adjustable double ended wrench”, issued on May 10,1995, discloses an adjustable wrench of which the width of the jaw canbe quickly adjusted. During the adjustment of the width of the jaw, theworm and the worm gear are first separated by one hand, then the movablebody is adjusted to a desired position by the other hand, and finallythe worm and the worm gear should be arranged to engage with each other.This kind of wrench overcomes to some extent the abovementioned defectsof the adjustable wrench. However, the wrench must be operated with bothhands, which could be further improved.

Moreover, an adjustable open end wrench is also disclosed in U.S. Pat.No. 3,555,939. A slot is provided along one side of a handle of astationary body of the adjustable wrench to communicate with a cavityfor receiving a worm gear. A helical shaft is provided in the slot. Abevel gear is provided at an end of the helical shaft close to thecavity to intermeshes with another bevel gear disposed at an end of theworm. A thumb button control is provided at the handle, an end of whichis slidable along a groove of the worm. In this way, while the thumbbutton control is pushed, the worm will rotate to in turn drive themovable body to move. This type of wrench can be adjusted by one hand.However, this adjustable open end wrench is relatively complex toconstruct and incurs a high cost.

BRIEF SUMMARY OF THE INVENTION

To overcome the shortcomings in the prior art as described above, thepresent invention provides an adjustable wrench which can rapidly beadjusted to any desired position with a simple operation by one hand,and can be manufactured with a sample process and a low cost.

To accomplish the foregoing object, the present invention provides anadjustable wrench for adjusting the width of a jaw quickly. The wrenchof the invention comprises a stationary body having a chamber disposedat an upper portion thereof; a movable body having a worm disposed at alower portion thereof, the worm being transversely movable inside thechamber; a driving mechanism located within the chamber, including aworm gear engaging the worm, a worm gear shaft, a first gearlocatedcoaxially at an end of the worm gear shaft of the worm gear, aconnection shaft located under and parallel to the worm gear shaft, asecond gear mounted at an end of the connection shaft engaging the firstgear; and a traction mechanism connected to the connection shaft, thetraction mechanism driving the connection shaft to rotate so that thesecond gear drives the first gear to rotate, thereby rendering the wormto move within the chamber.

The driving mechanism of the adjustable wrench of the present inventionmay further include two joint flakes with which the worm gear and thedriving mechanism can be integrated. Two circular holes are providedrespectively at each joint flake to receive the two ends of the wormgear shaft and those of the connection shaft. The worm gear shaft andthe connection shaft are rotatable within the circular holes.

According to a preferred embodiment of the present invention, thestationary body further includes an elongated cavity disposed at a sideof a handle of the stationary body, and the traction mechanism includesa guiding wheel placed within the elongated cavity at an end thereofaway from the chamber, and a driving rope wrapped around the guidingwheel and connected to the connection shaft. Preferably, the drivingrope is made of high strength and durable materials, and is of a littlebit elasticity. A control button is secured at a section of the drivingrope.

In a preferred embodiment, the driving rope is tightly wound in adirection around the connection shaft close to the second worm gear, andis then tightly wound in an opposite direction around the connectionshaft after wrapped around the guiding wheel.

The adjustable wrench of the present invention may further include acover plate having a shape corresponding to a peripheral shape of thechamber and the elongated cavity. An elongated opening is formed at thecover plate so that the control button is shown up therethrough. Thecover plate is secured at the stationary body by means of a joint memberfor covering the chamber and the elongated cavity.

Moreover, according to the adjustable wrench of the present invention, asquare through hole may be provided at the handle of the stationary bodyto allow insertion of a handle of a socket wrench.

In the present invention, the movement of the movable body is realizedby pulling the driving rope to quickly rotate the worm instead of bymanually turning the worm in the prior art. Thus, the adjustment of themoveable body can be accomplished in a more speedy and convenient mannerjust by one hand. When an object is turned, the movable body isself-locked through the cooperation of the worm and the worm gear, whichmakes the wrench reliable in operation. Moreover, the present inventionemploys spur gears rather than bevel gears in the prior art such thatthe wrench is relatively simple in construction, and also uses thedriving rope to realize the driving mechanism, which can further lowerthe cost.

BRIEF DESCRIPTION OF THE DRAWINGS

With reference to the drawings, the embodiments of the present inventionwill be further described as follows.

FIG. 1 is a schematic view showing the structure of an adjustable wrenchaccording to one embodiment of the present invention;

FIG. 2 is an enlarged sectional view of FIG. 1;

FIG. 3 is a schematic view showing a connection structure of the drivingrope in FIG. 2; and

FIG. 4 illustrates the structure of a cover plate according to oneembodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

As shown in FIG. 1, an adjustable wrench of an embodiment of the presentinvention includes a stationary body 1 and a movable body 2. A worm 13is disposed at a lower portion of the movable body 2. A chamber 12 isprovided at an upper portion of the stationary body 1, which is of asquare shape but apparently may be of other suitable shapes. The worm 13with a section thereof can transversely move within the chamber 12 toengage a worm gear 10 disposed within the chamber 12. By rotating theworm gear 10, the worm 13 can move in a left-and-right direction withrespect to the stationary body, thereby causing the movable body to movein the same direction. These elements of the adjustable wrench are thesame as those in the prior art.

In this embodiment of the present invention, a driving mechanism 100 isprovided within the chamber 12. As shown in FIGS. 1 and 2, the drivingmechanism 100 includes: the worm gear 10, a gear 3, a gear 4 and aconnection shaft 9. The worm gear 10 engages the worm 13 of the movablebody 2. By rotating the worm gear 10, the worm 13 is driven to movewithin the chamber 12 in a left-and-right direction, hereby adjusting adistance between the movable body and the stationary body. The worm gear10 has a worm gear shaft 20. An end of the worm gear shaft 20 isrotatablely connected to a side wall of the chamber 12, while anotherend of the worm gear shaft 20 is fixedly connected to the gear 3. Theconnection shaft 9 is disposed under and the worm gear shaft 20 inparallel. The gear 4 is mounted on the connection shaft 9 to engage thegear 3. When the connection shaft 9 is rotated under a force, the gear 4mounted thereon is further driven to rotate, thereby rotating the gear3, which in turn renders the worm gear 10 to rotate. In this way, theadjustment of the width of the jaw is reached.

In the embodiment, a traction mechanism 200 connected to the drivingmechanism 100 is provided so that a force can be easily applied to theconnection shaft 9. As shown in FIG. 1, an elongated cavity 11communicated with the chamber 12 is formed at a side of a handle 8 ofthe stationary body 1. The traction mechanism 200 is placed in thechamber 12 and the elongated cavity 11. A guiding wheel 7 is disposed ata side portion of the elongated cavity 11 away from the chamber 12. Adriving rope 5 is provided within the elongated cavity 11, which isconnected to the driving mechanism 100 through the guiding wheel 7.

Various methods, which permit free rotation of the gear 4 in either aclockwise or a counter clockwise direction, can be used to realize theconnection between the driving rope 5 and the driving mechanism 100. Toachieve this purpose, in a preferred embodiment, the driving rope 5 isfirst wound around the connection shaft 9 with an end thereof at asection of the connection shaft 9 close to the gear 4, and then woundaround a rotating member with another end. For example, in FIG. 3, therotating member is the connection shaft 9 itself, and in this caseanother end of the driving rope 5 is wound around a section of theconnection shaft 9 away from the gear 4 in an opposite direction afterwrapped around the guiding wheel 7. Preferably, the driving rope 5 ismade of high strength and durable materials. The rope can be of a littlebit flexibility, so that it can be always tightly disposed between therotating member and the guiding wheel 7.

A control button 6 is disposed at the driving rope 5 so that the drivingrope 5 can be controlled by moving the control button 6 in either aforward or a rearward direction. As shown in FIG. 3, the control button6 can be disposed in a proper position of a side of the driving rope 5with respect to the guiding wheel 7. For convenient operation, thecontrol button 6 is preferably of a rectangular shape which is slightlysmaller in width than the elongated cavity 11, so that the controlbutton 6 can be placed in and moved along the elongated cavity 11.Moreover, a groove 61 is provided along a longitude direction at a sideof the control button 6 facing to the elongated cavity 11. A side of thedriving rope 5 at which the control button 6 is not positioned isinserted into the groove 61, and is movable along the longitudedirection of the groove 61. Thus, the movement of the driving rope 5 canbe readily controlled to thereby improve operational reliability of theadjustable wrench.

In operation, the control button 6 is pushed to pull the driving rope 5so as to rotate the connection shaft 9, which renders the gear 4 torotate. The gear 3 engaged with the gear 4 is then driven to rotate,which in turn drives the worm gear 10 to rotate. The worm gear 10 drivesthe worm draft 13 at the lower portion of the movable body 2 to rotate,hereby making the movable body 2 move in a left-and-right direction. Thepushing of the control button 6 is stopped until the movable body 2 isadjusted to a proper position, and the self-locking effect between theworm and the worm gear will make the movable body 2 locked. When themovable body 2 is intended to be moved in an opposite direction, thecontrol button 6 should be pushed in an opposite direction, theconnection shaft 9 and the worm gear 10 will be rotated in an oppositemanner, and thus the moveable body will also be moved in an oppositedirection.

According to another preferred embodiment of the present invention, tworigid joint flakes 15 and 15′ are provided as shown in FIGS. 1 and 3.Two circular holes 16 and 17 are provided at the joint flake 15 whileother two circular holes 16′ and 17′ are provided at the joint flake 15in positions corresponding to the circular holes 16 and 17, to form twopairs of circular holes 16 and 16′, and 17 and 17′. In such a way, twoends of the worm gear shaft 20 and those of the connection shaft 9 arerespectively rotatably inserted into the circular holes 16 and 16′, and17 and 17′. Thus, the worm gear 10 and the driving mechanism 100 can beassembled together, and can be put into and taken off from the chamber12 of the stationary body 1 as a whole, and thereby is convenient formanufacture and maintenance.

According to another preferred embodiment of the present invention, acover plate 18 is further provided on the elongated cavity 11 and thechamber 12 of the stationary body 1. As shown in FIG. 1, the cover plate18 has a shape corresponding to a peripheral shape of the chamber 12 andthe elongated cavity 11. An elongated slot 19 is formed at the coverplate 18 for showing up the control button 6 which permits a user tooperate by hand. The length of the elongated slot 19 is configuredwithout affecting the movement of the control button 6 within theelongated cavity 11 when adjusting the width of the jaw. The cover plate18 can be secured at the stationary body through a joint member forcovering the chamber and the elongated cavity. For example, screw bores21 and 22 are provided in a proper position of the cover plate 18 andthe stationary body 1, respectively, and thus the cover plate 18 and thestationary body 1 can be coupled together by means of a screw or a boltor the like. This configuration provides a neat appearance of thewrench, and is suitable to protect all elements within the chamber 12and the elongated cavity 11.

Moreover, according to a further preferred embodiment of the presentinvention, a square through hole 14 is provided at the handle 8 of thestationary body 1 to allow insertion of a handle of a socket wrench.

The adjustable wrench of the present invention by setting conventionalgears 3 and 4 to provide a linear connection for driving the movement ofthe jaw, overcomes the deficiencies of the prior art. The wrench of theinvention can be manufactured in a low cost, and kept a long life foruse. Meanwhile, the driving rope of the present invention makes thewrench more convenient.

1. An adjustable wrench for quickly adjusting the width of a jaw,comprising: a stationary body having a chamber at an upper portionthereof; a movable body having a worm at a lower portion thereof, beingmovable transversely inside the chamber; a driving mechanism locatedwithin the chamber, including: a worm gear with a worm gear shaft,engaging the worm, a first gear mounted at an end of the worm gear shaftof the worm gear, a connection shaft located under the worm gear shaftin parallel, and a second gear mounted at an end of the connection shaftto engage with the first gear; and a traction mechanism connected to theconnection shaft, wherein the traction mechanism drives the second gearto rotate by driving the connection shaft, which drives the first gearto rotate, thereby rendering the worm to move inside the chamber, andwherein the driving mechanism further includes two joint flakes forintegrating the worm gear and the driving mechanism and holes providedin corresponding positions of each of the joint flakes, respectively, sothat both ends of the worm gear shaft and those of the connection shaftcan be rotatably installed in the holes.
 2. The adjustable wrench ofclaim 1, wherein the stationary body includes an elongated cavitypositioned at a side of a handle of the stationary body, and thetraction mechanism includes a guiding wheel disposed within theelongated cavity away from the chamber and a driving rope connected tothe connection shaft via the guiding wheel.
 3. The adjustable wrench ofclaim 2, wherein the driving rope, with an end thereof, is tightly woundaround the connection shaft in a direction, and is tightly wound aroundthe connection shaft in an opposite direction with another end thereof,after wrapped around the guiding wheel.
 4. The adjustable wrench ofclaim 3, wherein the driving rope is made of materials with a highstrength and slight flexibility.
 5. The adjustable wrench of claim 3,wherein a control button is provided at a section of the driving rope.6. The adjustable wrench of claim 5, wherein the traction mechanismfurther includes a cover plate for covering the chamber and theelongated cavity, having a shape corresponding to a peripheral shape ofthe chamber and the elongated cavity, an elongated slot is provided atthe cover plate for exposing the control button, and the cover plate issecured at the stationary body by a joint member.
 7. The adjustablewrench of claim 6, wherein the joint member includes screw boresdisposed at the cover plate and the stationary body, respectively, andscrews or bolts matched with the screw bores.
 8. The adjustable wrenchof claim 1, wherein a through hole is provided at the handle.